1. Technical Field
The present invention relates to atomic frequency acquiring apparatuses and atomic clocks.
2. Related Art
Atomic clocks that control the frequency of an oscillator based on the natural frequency of atoms are more often used in various situations instead of conventional quartz oscillators. Above all, coherent population trapping (CPT) type atomic clocks are suitable for miniaturization and power-saving, and are expected to be applied to cellular phones or other devices in future. The accuracy of an atomic clock may be deteriorated unless its gas cell that encloses atomic gas, laser emission section and photodetector section are accurately aligned with one another on a substrate. The complexity in alignment works is one of the causes that lower the mass production efficiency in manufacturing electronic apparatuses that incorporate atomic clocks. In this connection, U.S. Pat. No. 6,900,702 and U.S. Pat. No. 6,570,459 are examples of related art.